What is Cavitation?
If you’ve ever cracked your knuckles, you’ve created cavitation. This phenomenon can occur infrequently during the distraction procedure. As the distractor device imposes a lateral distractive force on the hips, the creation of negative pressure can cause a void to form in the synovial fluid in the joint. This void appears as an air bubble on the radiograph. Cavitation is not painful and does not cause short or long term damage to the joint. It occurs infrequently, and resolves within 24 hours. Cavitation is problematic only because it causes the DI measurement to be unreliable. A cavitated joint can have a false increase in the DI.
Cavitation occurs in liquid when bubbles form and implode in pump systems or around propellers. Pumps put liquid under pressure, but if the pressure of the substance drops or its temperature increases, it begins to vaporize, just like boiling water. Yet in such a small, sensitive system, the bubbles can’t escape so they implode, causing physical damage to parts of the pump or propeller. A combination of temperature and pressure constraints will result in cavitation in any system. No manufacturer or industrial technician wants to run pumps that keep getting affected by cavitation, as it will permanently damage the chambers of the device. The vaporization actually causes a loud, rocky noise because the bubbles are imploding and making the liquid move faster than the speed of sound! Inside every pump, there is a propeller that draws liquid from one side of the chamber to the other. The liquid normally continues out through a valve so it can do another job in a different part of the machin
In simplest terms, cavitation is the process in which a liquid changes to a vapor due to a reduction in pressure. Consider the diagram below. Each point in the diagram represents a specific pair of temperature and pressure. For example, typical room conditions, with a pressure of 1 atmosphere (14.7 pounds per square inch) and a tempearature of 20 degrees C (68 degrees F), are represented by point A. Suppose we have a water sample at point A, and we begin increasing its temperature. Eventually, its temperature will reach a point (100 degrees C) where it will change from a liquid to a vapor. The water boils. In the diagram above, this corresponds to process A->B. Note that this process crosses the “vaporization line”, indicating that the water has changed from a liquid to a vapor. If you’ve ever read instructions for cooking food at high elevation, you know that the recommended cooking times are significantly longer. This is because water boils at a lower temperature at high elevations.
Cavitation means that air cavities are forming in the liquid that we are pumping. When these cavities form at the suction of a pressure washer pump several things happen all at once. We experience a loss in capacity. The efficiency drops. The thousands of cavities or bubbles will collapse (explode) when they pass into the higher regions of pressure causing noise, vibration, and damage to many of the components. In my case it produced an explosion within the pump strong enough to blow a hole through a metal manfold casing. These cavities form for four basic reasons and it is common practice to lump all of them into the general classification of cavitation. In no particular order these are: Vaporization No Inlet flow or interruption of flow Air ingestion Flow turbulence About Vaporization A fluid vaporizes when its temperature is too high. .In designing pumps the assumption that fresh water at 68 degrees Fahrenheit (20 degrees Centigrade) is the fluid being pumped. You can lower the flui
“Cavitation” is the rapid formation and collapse of millions of tiny bubbles (or cavities) in a liquid. Cavitation is produced by the alternating high and low pressure waves generated by high frequency (ultrasonic) sound. During the low pressure phase, these bubbles grow from microscopic size until, during the high pressure phase, they are compressed and implode.